X2Y® Filter & Decoupling Capacitors |
|
X2Y® filter capacitors employ a unique, patented low inductance design featuring two balanced capacitors that are immune to temperature, voltage and aging performance differences. The components offer superior decoupling and EMI filtering performance, virtually eliminate parasitics, and can replace multiple capacitors and inductors saving board space and reducing assembly costs.
|
 |
|
Advantages
- One device for EMI suppression or decoupling
- Replace up to 7 components with one X2Y
- Differential and common mode attenuation
- Matched capacitance line to ground, both lines
- Low inductance due to cancellation effect
|
Applications
- FPGA / ASIC / μ-P Decoupling
- DDR Memory Decoupling
- Amplifier Filter & Decoupling
- High Speed Data Filtering
- Cellular Handsets
|
|
Common Traits with Conventional MLCC
- Same component sizes (0603, 0805, 1206, etc.)
- Same pick and place equipment
- Same voltage ratings
- Same dielectric, electrode and termination materials
- Same industry test standards for component reliability
|
X2Y® components share many common traits with conventional multi-layer ceramic capacitors (MLCC) to facilitate adoption by end-users into their manufacturing processes.
|
The X2Y® Design - A Balanced, Low ESL, "Capacitor Circuit"
 |
X2Y® Circuit 1: Filtering
Circuit 1 connects the X2Y® filter capacitor across two signal lines. Common-mode noise is filtered to ground (or reference) by the two Y-capacitors, A & B. Because X2Y® is a balanced circuit that is tightly matched in both phase and magnitude with respect to ground, common-to-differential mode noise conversion is minimized and any differential-mode noise is cancelled within the device. The low inductance of the capacitors extends their high frequency attenuation considerably over discrete MLCs.
|
 |
X2Y® Circuit 2: Power Bypass / Decoupling
Circuit 2 connects the A & B capacitors in parallel doubling the total capacitance while reducing the inductance. X2Y® capacitors exhibit up to 1/10th the device inductance and 1/5th the mounted inductance of similar sized MLC capcitors enabling high-performance bypass networks with far fewer components and vias. Low ESL delivers improved High Frequency performance into the GHz range.
|
GSM RFI Attenuation in Audio & Analog
GSM handsets transmit in the 850 and 1850 MHz bands using a TDMA pulse rate of 217Hz. These signals cause the GSM buzz heard in a wide range of audio products from headphones to concert hall PA systems or "silent" signal errors created in medical, industrial process control, and security applications. Testing was conducted where an 840MHz GSM handset signal was delivered to the inputs of three different amplifier test circuit configurations shown below whose outputs were measured on a HF spectrum analyzer.
- No input filter, 2 discrete MLC 100nF power bypass caps.
- 2 discrete MLC 1nF input filter, 2 discrete MLC 100nF power bypass caps.
- A single X2Y 1nF input filter, a single X2Y 100nF power bypass cap.
|
 |
|
Technical Notes 